Leo III of Byzantium

Leo III "the Isaurian" of Byzantium (685-18 June 741) was the Emperor of the Byzantine Empire from 717 to 741, succeeding Theodosius III of Byzantium and preceding Constantine V of Byzantium.

Biography
Leo was born to the House of Isauros, and he joined the army of Justinian II of Byzantium, who was advancing on Constantinople with 100,000 Bulgarian troops. He was later sent to Alania and Lazica to secure support for a war against the Umayyad Caliphate, and under Anastasius II of Byzantium he was made strategos of the Theme of Anatolia. In 717 he forced the abdication of Theodosius III of Byzantium and became emperor, holding off Maslama's siege of the city from 717-718. Afterwards, he focused on iconoclasm, destroying religious imagery, which he saw as sacreligious.